Research On Multi-Objective Planning Of Active Distribution Network

With the increasing penetration of distributed generation at all levels of power system, the planning and operation mode of distribution network has become relatively complex, also have a greater impact on the economy and reliability of distribution network. However, there are many problems in the traditional distribution network which is not conducive to optimization and adjustment of energy structure. For example, the network is weak, the automation level is not high,renewable energy consumption is insufficient and so on. Seriously restricted the high penetration of distributed power supply, is not conducive to the optimization of energy structure adjustment. In response to this situation, active distribution network technology came into being, which is compatible with the power grid,improves the acceptance ability of renewable energy, and promotes the utilization of green energy.By means of location and capacity of distributed power supply and energy storage system by unified planning,the research of the active distribution network,how to make it in the condition of security, stability and economic operation, by means of unified planning of the location and capacity of distributed generation and energy storage system. A multi-objective planning model of distribution network model is developed with an overall consideration of the economy and reliability.The investment cost of DG, battery and tie lines, voltage quality index and lack of power supply as the objective functions. Improved NSGA- ? solving method was proposed to get pareto optimal solution set of the multi-objective function, and fuzzy set theory was used to find the optimal solution. Finally, the model is used in a IEEE69-bus distribution system planning. The example results shows the validity and correctness of the model and algorithm.Optimal operation of active distribution system is conducive to achieve the complete consumption of intermittent renewable energy, improve the economy of system operation, and reduce the difference between peak and valley of load.Starting from the economy and peak load shifting of active distribution system, a mathematical model for the optimal operation of active distribution system composed of two objective functions such as economic cost and payload variancewas established. Improved NSGA- ? solving method was proposed to get pareto optimal solution set of the multi-objective function, and fuzzy set theory was used to find the optimal solution. Finally, the programming examples of the third chapter shows the validity and correctness of the model and algorithm.Finally, based on the analysis and summary of existing research of active distribution network, the future research direction and development trend is pointed out, and the multi-objective planning and optimization operation of active distribution network further research content is proposed.